arXiv is an e-print service in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. It provides access to more the 1.3 million e-prints. The Max Planck Society is a member institution of arXiv.

The numerical database DETHERM provides thermophysical property data, which are indispensable for construction and design of chemical apparatus, plants and processes. DETHERM contains literature values, together with bibliographical information, descriptors and abstracts. The following properties for pure compounds and for mixtures are stored: 1) phase equilibrium data, 2) vapor pressures and critical data, 3) thermodynamic properties, 4) transport properties, 5) surface tensions, 6) electrolyte data.

GeoReM is a Max Planck Institute database for reference materials of geological and environmental interest, such as rock powders, synthetic and natural glasses as well as mineral, isotopic, biological, river water and seawater reference materials. It contains published analytical data and compilation values (major and trace element concentrations and mass fractions, radiogenic and stable isotope ratios). GeoReM covers all important metadata about the analytical values such as uncertainty, analytical method and laboratory. Sample information and references are also included. GeoReM contains almost 3,400 reference materials, about 46,200 analyses from almost 10,000 papers, and preferred analytical values (State: November 2017).

The database GEOROC is maintained by the Geoscience Centre at Göttingen University. The database is a comprehensive collection of published analyses of volcanic rocks and mantle xenoliths. It contains major and trace element concentrations, radiogenic and nonradiogenic isotope ratios as well as analytical ages for whole rocks, glasses, minerals and inclusions. Samples come from 11 different geological settings. Metadata include, among others, geographic location with latitude and longitude, rock class and rock type, alteration grade, analytical method, laboratory, reference materials and references.

ICSD is the world’s largest database for fully identified inorganic crystal structures. It currently contains about 193,000 peer-reviewed data entries including their atomic coordinates. Updates are made twice a year (in spring and in fall) with data taken from scientific journals and other sources. Thanks to these many heterogeneous data sources the database has a wide coverage. ICSD is also updated retroactively. The oldest records date back to the year 1913 and contain information from publications by William Henry Bragg and his son.

The series comprises articles and tables of data relevant to crystallographic research and to applications of crystallographic methods in all sciences concerned with the structure and properties of materials. Emphasis is given to symmetry, diffraction methods and techniques of crystal structure determination, and the physical and chemical properties of crystals. Each volume also contains discussions of theory, practical explanations and examples, all of which are useful for teaching. The following volumes are available: * Volume A - Space-group symmetry * Volume A1 - Symmetry relations between space groups * Volume B - Reciprocal space * Volume C - Mathematical, physical and chemical tables * Volume D - Physical properties of crystals * Volume E - Subperiodic groups * Volume F - Crystallography of biological macromolecules * Volume G - Definition and exchange of crystallographic data

SpringerMaterials is based on the Landolt-Börnstein New Series, the unique, fully evaluated data collection in all areas of physical sciences and engineering. It is a systematic and comprehensive resource of selected and critically assessed data explained in their scientific context.

The MPI-Mainz-UV-VIS Spectral Atlas is a comprehensive collection of absorption cross sections for gaseous molecules and radicals, primarily relevant to atmospheric research, from measurements performed during the last nine decades. The individual data sets were collected from the original publications, either copied from tabulations, or read from figures in those cases where numerical data could no longer be obtained. Other sources rely on the internal databases of several research centers dealing with atmospheric chemistry and/or molecular spectroscopy. Numerous excellent high-resolution spectra were obtained from personal communications with the scientists.

Zenodo is an open data repository, developed and operated by CERN. It is an catch-all repository, that welcomes research from all over the world, and from every discipline. Zenodo does not impose any requirements on format, size, access restrictions or licence. A digital object identifier (DOI) is automatically assigned to all Zenodo files and it is integrated into reporting for research funded by the European Commission.